1. Field of the Invention
The present invention relates to an electric motor, which obtains maximum rotary power and force from low electric power, thus greatly improving energy efficiency.
The present invention relates to an electric motor, comprising a stator, in which field magnets are fixedly and radially installed on a circular panel-shaped base, a coaxial cylindrical rotor coupled to a shaft, which penetrates through a center of the base, and configured to allow the stator to be located at an inside thereof, the rotor being configured such that magnets, having different polarities to form each pair, are attached on an outer cylinder and an inner cylinder of the rotor and are arranged opposite each other, a cover coupled to the circular panel-shaped base to cover the rotor while causing the shaft of the rotor to penetrate through and protrude from the cover, a rotary magnet plate coupled to the shaft on a top of the cover, and provided with a number of magnets corresponding to a number of pairs of the rotor magnets, magnetic sensors formed on the top of the cover and configured to come into contact with the rotary magnet plate, and a current control device configured to control a magnetization direction of the field magnets of the stator using a rotation angle signal detected by the magnetic sensors, wherein the rotor magnets attached on the outer cylinder and the inner cylinder of the rotor have different polarities to form each pair and are arranged opposite each other, and respective pairs of rotor magnets are arranged on the outer and inner cylinders while being spaced apart from each other by a predetermined interval.
2. Description of the Related Art
The present invention relates to an electric motor, which is an improvement of Korean Patent No. 10-0417637.
Korean Patent No. 10-0417637 relates to an electric motor, which controls the current flowing through a field winding and the polarity variation time in proportion to the speed of rotation of the motor, so that rotary power is increased by causing both an attractive force and a repulsive force to be at work when a field core and the center of rotor magnets are closest to each other after the field core is completely magnetized, and in which a rotor with N and S-pole permanent magnets attached thereto is formed by integrating two magnets having different diameters into a single body, but the field core is arranged between the two rotor magnets, so that an attractive force and a repulsive force bidirectionally act between a magnetized field core and the two rotor magnets in a dual mode, thus obtaining maximum rotary power from low electric power.
Generally, a motor is a rotating device for converting electrical energy into mechanical energy. A DC motor driven by DC power typically includes a stator composed of permanent magnets and fixedly installed on the outer side of a main body, a rotor rotated by an attractive force and a repulsive force relative to the stator, and a brush coming into contact with the rotor to supply current to the coils, wherein the rotor includes a core fixedly installed on a shaft and configured to rotate, the coils wound around the core and configured to allow the core to have an electromagnetic property because of supplied current, and a commutator configured to supply current to the coil.
In such a conventional DC motor, the core, which is fixedly installed on the shaft and is composed of a plurality of folders, coils wound around the folders, and the commutator for supplying current to the coils, are connected to constitute the rotator, so that the construction of the rotator is complicated, and a large load is imposed at the time of rotation, thus decreasing rotary power.
Further, in the conventional DC motor, since half of the folders formed on the core are fixedly maintained as N poles and the remaining half are fixedly maintained as S poles, an attractive force and a repulsive force act only on the ends of the permanent magnets of the stator and on some of the folders of the rotator placed at the ends, and thus uniform rotary power is maintained. However, in order to obtain higher rotary power, a lot of current must be supplied to the coils through the commutator, thus resulting in a problem in which power consumption increases.
In particular, recently, electric vehicles have been rapidly developed, and a DC electric motor in such an electric vehicle is an essential power generation means, so that the development of DC electric motors capable of obtaining high rotary power and force from low electric power is urgently required.
For this purpose, the present applicant proposed technology disclosed in Korean Patent Nos. 0269035 and 0417637, and intends to enhance the energy efficiency of a motor by further improving on the above patents.